2 x cellulose folded filter cassettes with insertion rib, filter material IFA (BIA) tested in accordance with dust class „M“ – Filter surface area: 8600 cm 2 – Material: polyester – Dust retention: 99.93 % (to 1μ 99.9 %) Folded filter cassette with glued in, optimised polyester filter material and inserted rubber seal. For vacuuming industrial dust, sawdust, brick, drilling and milling dust and other similar substances. Suitable for damp dust and liquids (fleece material). Depending on the type of dust Safety vacuum cleaner must be used.